Board of Governors of the Federal Reserve System (U.S.), 1935-. "Explanatory Note," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "December 14, 1990," G.17 Industrial Production and Capacity Utilization (1990-12-14) : 18-18. https://fraser.stlouisfed.org/title/77/item/63585/toc/454742 , accessed on May 9, 2024.